Laser cutting 3mm black matte acrylic sheet, get three panels.
Cropped white A4 paper into small pieces, small enough to be able to cover just a small hole on the acrylic. After cutting the number by how much they want to light up lamps to decide.
Coverd the small white pieces of paper attached to the hole on acylic which have LED.
Coverd the black washed kraft paper to the holes which have no LED.
Check the acrylic, use 3M black tape to fix the leaky places.
Pastethe acrylic panels attached to the glass.
Welding LED, then posted them to the position you just posted write paper.
Connecting the LED and Seeeduino + Base shield, and fired into the corresponding program.
Access to power, start, completion.
ps：The relevant code and design documents